1. FIELD OF THE INVENTION
The present invention generally relates to an image processing apparatus. More specifically, the present invention is directed to an image processing apparatus suitable for detecting the number of waiting passengers in a group-controlled or supervised elevator system.
2. DESCRIPTION OF THE BACKGROUND ART
Various types of apparatus for detecting an object by processing image information have been proposed. For instance, as a traffic flow measuring system for aiming at an automobile, one conventional technique has been opened in a publication of The Institute of Electronics and Communication Engineers of Japan, '85/3 Vol. J68-D No. 3, pages 308 to 315 (referred to as a "publication 1"), in which the images photographed over the highways are processed based on the algorithm with various defined constants (parameters).
Also, another conventional image processing system as an apparatus for measuring man flows has been described in another publication of The Institute of Electronics and Communication Engineers of Japan, IE80-73 (1980, 11) (referred to as a "publication 2"), in which various sorts of threshold values and weight employed in the image processing algorithm are determined by way of the learning and then the image process operation is performed by utilizing these determined threshold values and weight.
Furthermore, as disclosed in JP-A-1-241667 (referred to as a "publication 3"), when a neural network is employed in the speech recognition technique, the speech pattern whose answer has been known is inputted in the learning mode, and the weight (coupling) coefficients are corrected in such a manner that the difference between this speech pattern and the prepared answer is reduced to be zero.
As previously described, in accordance with the above-mentioned conventional techniques, there are provided a large quantity of input patterns the answers of which have been recognized with respect to the processed results, and these input patterns are repeatedly entered so as to obtain the desirable answer. As a consequence, even when the answers could be obtained with respect to the prepared input patterns, the conventional image processing apparatuses cannot follow such cases that previously unexpected changes happen to occur in the environment from which the input information can be obtained.
For instance, there is such a conventional image processing apparatus which cannot follow such an environment that variations are given to the background (will be discussed late) and then produces the incorrect outputs.